Computers have evolved from room-sized apparatus to desktop personal computers and then to devices which have a size similar to or smaller than a three-ringed notebook, often referred to as portable computers. Although the smaller computers work great as portable devices while away from the office, the reduced size of the computer often produced discomfort for the user's hands and wrists while using the keyboard. This led to a need to provide a wrist or palm rest for the user at the same level as the top of the keyboard. Placing a separate palm rest in front of the keyboard has addressed this need.
In reducing the computer to a portable size, certain input devices commonly associated with larger computer systems were combined in order to provide a more compact device. For example, the numeric keypad usually found on full size desktop keyboards was eliminated from portable computer keyboards to save space. In order to input numbers from portable computers, the numbers across the top of the alphanumeric keyboard were used. However, unless the user is familiar with the layout of the alphanumeric keyboard and is a reasonably good typist, data entry can be inconvenient and time consuming. As a result, stand-alone numeric keypads became available as after market input peripheral devices. Unfortunately, the need to carry an additional device along with the portable computer while away from the office has detracted from the portability of the portable computer.
Another solution to the elimination of the separate numeric keypad on the portable computer keyboards was to place "embedded" keys in the configuration of a typical numeric keypad within the alpha keys of the keyboard. The embedded keys are available only after a "Num Lock" key on the keyboard is activated. After the Num Lock key has been activated, the embedded keys on the keyboard respond as numeric, rather than alpha, keys. Unfortunately, this typically means that at least eight letters of the alphabet, including up to three vowels, are not available for use when the Num Lock key is activated. As a practical matter, this turns the whole keyboard into a numeric keypad and renders it useless for other purposes. This is undesirable since users often switch back and forth between tasks and need to retain the complete functionality of the alpha keys on the keyboard at all times.
While these types of embedded numeric keypads do provide access to numeric keys in a numeric keypad configuration, many users of portable computers would prefer the use of a separate numeric keypad which can be used simultaneously with the other alphanumeric and function keys on the keyboard. A separate non-embedded numeric keypad is particularly desirable for use with accounting and spreadsheet software programs.